<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        p{
            color: aqua;
        }
        .hello{
            font-weight: bolder;
        }
    </style>
</head>
<body>
<h1 id="first">我的界面</h1>
<div>
    <p>你好</p>
    <p class="hello">hello html</p>
</div>
<h3 class="hello"></h3>
<p class="hello" style="color: orange;">hello html</p>
<a href="//baidu.com"></a>
<script src="./dom.js"></script>
</body>
</html>